Serializing GameObject Data with XML, Adaptation

(Apologies for the large code dump but it's imperative i show every edit I've made to the original source code in an attempt to adapt it.) I'm desperately trying to find a way of serializing gameobject data in a 2D game where the player can place objects and build buildings. After alot of failed attempts and research i discovered this code in this question on the forums provided by @TonyLi and @Slimy619. It works perfectly for serializing ONE gameobject and one gameobject only, but whenever i try to adapt it to handle more than one specific type, they all revert immediately back to the ONE gameobject the system is designed to handle.

My Question is - How do i adapt this code to handle more than one type of GameObject? Here's what i've tried so far and the issues i've identified; (C#)

 using UnityEngine;
 using System.Collections;
 using System.Collections.Generic;
 //using System.Xml; 
 using System.Xml.Serialization;
 using System.IO; 
 //using System.Text; 
 
 public class SaveLoadSystem : MonoBehaviour {
     
     
     public GameObject CubeContainer;
     
     // Use this for initialization
     void Start () {
         
     }
     
     // Update is called once per frame
     void Update () {
         
     }
     
     public class CubeInfo
     {
         public string prefabName;
         public Vector3 position;
         //public Quaternion rotation;
         
         public CubeInfo()
         {
         }
         
         public CubeInfo(Transform cube ) 
         {
             prefabName = cube.name.Replace("(Clone)", string.Empty);
             position = cube.position;
             //rotation = cube.rotation;
         }
     }
     
     public class HigInfo
     {
         public string prefabName2;
         public Vector3 position2;
         
         public HigInfo()
         {
         }
         
         public HigInfo(Transform Hig)
         {
             prefabName2 = Hig.name.Replace("(Clone)", string.Empty);
             position2 = Hig.position;
         }
     }
     
     
     public class BuildingInfo
     { // Stores info about all the cubes.
         
         // Make a List holding objects of type CubeInfo
         public List<CubeInfo> cubeList;
         public List<HigInfo> HigList;
         
         public BuildingInfo() 
         {
             // Make a new instance of the List "cubeList"
         }
         
         public BuildingInfo(GameObject rootObject) 
         {
             cubeList = new List<CubeInfo>();
             HigList = new List<HigInfo>();
             
             foreach (Transform child in rootObject.transform) 
             {
                 cubeList.Add (new CubeInfo(child));
                 print (child);
             }
             
             foreach (Transform child in rootObject.transform) 
             {
                 HigList.Add (new HigInfo(child));
                 print (child);
             }
         }
         
         public void reload(GameObject rootObject)
         {
             // Rebuild the cubes after loading building info:
             foreach (var cubeInfo in cubeList) 
             {
                 GameObject cube = Instantiate(Resources.Load(cubeInfo.prefabName),cubeInfo.position, Quaternion.identity) as GameObject;
                 cube.transform.parent = rootObject.transform;
             }
             
             foreach (var HigInfo in HigList) 
             {
                 GameObject Hig = Instantiate(Resources.Load(HigInfo.prefabName2),HigInfo.position2, Quaternion.identity) as GameObject;
                 Hig.transform.parent = rootObject.transform;
             }
         }
     }
     
     
     void Save(GameObject rootObject, string filename) 
     {
         BuildingInfo buildingInfo = new BuildingInfo(rootObject);
         XmlSerializer serializer = new XmlSerializer(typeof(BuildingInfo));
         TextWriter writer = new StreamWriter(filename);
         serializer.Serialize(writer, buildingInfo);
         writer.Close();
         print ("Objects saved into XML file\n");
     }
     
     void Load(GameObject rootObject, string filename) 
     {
         //        while(rootObject.transform.GetChildCount()>0)
         //        {
         //            GameObject.Destroy(rootObject.transform.GetChild (0));
         //        } 
         
         XmlSerializer serializer = new XmlSerializer(typeof(BuildingInfo));
         TextReader reader = new StreamReader(filename);
         BuildingInfo buildingInfo = serializer.Deserialize(reader) as BuildingInfo;
         buildingInfo.reload(rootObject);
         reader.Close();
         print ("Objects loaded from XML file\n");
     }
     
     void OnGUI()
     {
         if (GUI.Button (new Rect (30, 60, 150, 30), "Save State")) 
         {
             Save (CubeContainer, "savefile.xml");
         }
         
         if (GUI.Button (new Rect (30, 90, 150, 30), "Load State")) 
         {
             Load (CubeContainer, "savefile.xml");
         }
     }
 }

Using the Debug lines for (child) reveals in the inspector console window that the items are all being saved as "cube", in spite of the additions i've made. I've tried similarly including a Cube2 field and all the relevant parameters throughout the file without making a second cubeinfo (higinfo) class to no avail. The Hig gameobject in my resources folder merely gets renamed to cube and the game spawns instances of the first gameobject on Load. I am completely stumped. I haven't come across any other working method for saving instantiated gameobjects, If it's worth anything all i need to save is the location (vector3) sprite and collider of the object. Also worth mentioning this game is intended for PC and Android if its worth anything. I'd appreciate any possible insight anyone could offer.

Before saving-

After loading-